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swr` 23, 1930. L' K' BR^REN Re. 11,811

GEAR TRANSMISSION V l Original Filed Nov. 30, 1'926l 2 Sheets-Sheet 1 L. K. BRAREN GEAR TRANSMISSION originn Filed Nov'. so. 192s 2 Sheetsheet 2 Sept. 23, 1930.

H 3 325 J' 17g lol Hg. 7 Zaren/9 UQZ 71271671 Reiuued Sept. 23,. 1930 UNITED STATES Lonmrz xomian naman, or MUNICH, GERMANY, As'srenon cro 'rnin'rram aman# Re.` 17,811v

man DncxnL, PnzrsroNsmncnan-Ix UND mascnmmvramor. monica, ranma,

GERMANY,

GEAR TRANSMISSION Original No. 1,894,031, dated December 4, 1928, Serial No. 151,800, led November30,'1926, and' in Germany December 5, 1925. Application for reissue led April 24, 1930. Serial No. 447,071.

The invention relates to geartransmissions and has for its object to provide a transmis` sion with a fixed speed ratio of a very simle, compact and durable form. This object 1s attained by arranging one or a plurality of intermediate discs betweenthe fast'and slowly Vrotating members. This disc is mounted eccentrically on the fastv member and is provided on the lcircumference with a number of teeth to engage With a set of holding members, for instance-rollers. The teeth on the circumference form a continuous cycloidal curve or an equidistant to such a curve. The term cycloidal curve is meant to include trochoid, epicycloid, ep'itrochoid, hypocycloid and hypotrochoidcurves. The prolate type of the curve is of s eclal advantage for this purpose as it as no turning point and thereforea more favourable` acceleration. The load with the prolatev form of the curve furthermore is not transmitted on a single line of the disc during a longer period as is the case withthe normal curve.

Another object of my invention is to remove all bending straln from the fast as well as from the slow shaft which object is attained by providing a pluralitv of intermediate discs disposed angularlvy to each other to -compensate for the bending forces.

Another important object of my invention is to equalize the load of the transmitting pins which isattained by providing a supporting ring on the outside end of the pins and between the intermediate discs in case more than one are used. In case of severely loaded transmissions the ring may be supported radially.

I furthermore make according to my in vention all pins of such a diameter that they deflect a trifle under -load equalizin'g thus any possible inaccuracies in the form of the' curve or in the location of the pins.

Another object of my invention is to provide transmitting pins of the same number as there-are teeth in the intermediate discin order to attain a Very compact construction. When using a pluralit of discs the number of teeth must be divisible by the number of discs in order to be able to locate the bores for the transmitting pins in the teeth.

The above and various other important improvements will be hereinafter fully described and claimed. In order that this my invention may be more readily understood reference is made to the accompanying sheets of drawings which show howthe invention may be carried into practical effect.

Fig. 1 is a longitudinal section'of a gear transmission with two intermediate plates.

Fig. 2 is a cross section of the transmission shown in Figure 1;

Fig. 3 is a longitudinal section of a transmission with one intermediate plate.

Fig. 4 is a, cross section of a transmission as shown in Figure 2 but with special holdin means for the equalizing ring.

ig. 5 shows a different arrangement of the transmitting pins. and a single set of holding members for two intermediate discs.

Fig. 6 'shows the use ofan epicycloid for the teeth on the disc.

Fig. 7 shows the discwith choid.

Referring to the Figures land 2 the fast .rotating shaft 1v which for instance may be the shaft of an eleetromotor is fastened by a prolate trol a key 41 to a bushing 4which is journaled in a bore of the cover 7. A crank'shaft-42 fastened to the bushin 4' by a number. of key like projections 43 as two cranks 2 and 3 disposed at 180 to each other. shaft 42 is journaled in twov roller bearings 5 and 6 of which the first is supported by the cover 7 while the latter is carried by the slowly rotating shaft 8. Two intermediate discs 9 and IOare mounted on roller bea-rings 11 and 12 to turn freely on ythe cranks 2 an 3.

The discs 9 and 10ers fashioned on the circumference with a4 number of teeth the exact shape of whichl willbe described later. The teeth standin engagement with rollers 13 and 14 turnably mounted on pins 15 and 16. The pins 15 are fastened in the cover 7 while an equal number of pinsltv are fastened. in the housing 17. The number of rollers in engagement with each disc di'ers by one from the number of teeth. The

The erank- `tation is ldetermined by this relation. An

l epicycloid or epitrochoid is required when the number ofthe holding members-14 exceeds the' number of. teeth by one. The

crankshaft 42 and the-slowly rotating shaft 8 in this case rotate' in opposite directions. l-Vhen however the number ofthe holding members 14 is smaller b one than the number of teeth an hypocyc oid or hypotrochoid is required. Both shafts rotate in this case in the same direction. For transmitting` the turning moment from the discs tothe slowly rotatingr shaft or vice versa there are provided a number of pins 19 fastened in a flange 44 of the slow shaft .8. Holes 45 in identical number with the pins are bored in the discs. For heavy service the number of the holes 45 in the discs should correspond to the number of teeth as it thusbecomes possible to locate the holes in the teeth whereby the radius of the pins from the centerline is increased vand the load on the pins cor-` respondingly decreased. Where size is not of great importance the disc may be made larger in diameter and a different number of holes 45 be provided than there are teeth (see Figure 5). The rollers 13 and 14 in this case may be arranged on a single pin 15. To reduce the friction of the pins in the holes 45 rollers 2() and 21 are interposed. The diameter of the holes 45 is equal to the diameter of the rollers 2() plus twice the eccentricity of the cranks. The pins 19. 15 and 16 are dimensioned to deflect slightly under'the'load so as to equalize any'inaccuracies of manufacture.

In order to distribute the load equally on all pins rings 18, 22 and 23 are provided.

The ring 18 sup orts the free 4ends of the pins 15 and 16 w ich latter are spaced half a division apart in relation to each other. The ring 22 is arranged between the two vdiscs 9 and 10 and may be supported lradially in a ball bearingv46 for very heavy service. Another mode of supporting the rings 22 and 23 is shownon Figure 4 where two pins 24 and 25 a trifle smaller than the di'- ameter of the rollers 2() carry the rings. Normally such a support is ynot necessary.

The ring 23 finally is located over the endsof the pins 19, crosspins 47 holding the rings and the rollers 20.axia1ly.

Counterweights 26 and 27 on `the fast sleeve 4 and on the crankshaft 42 form a coupleto compensate for the couple caused by the discs 9 and 10.

" The slow shaft 8 is supported radially aiid held axially by two roller `bearings 48 and 49 in the housing 17. The cover 7 is fastened by screws 50 to the Yhousing 17 Y forming thus Aan oiland airtight container. Two openings 51 are provided of which one only is shown, the one for filling with lubrif.

cant and the other for determining the oil `passing through the roller bearing, a passage 164 permitting it to return to the oil about equal to 3/L of the radius r of the roll- .cumference of said disc forming a continulevel. The housing may be shaped to serve as end plate for an electromotor, thelarmature shaft being supported by the cover 7.

The transmissionshown in Figure 3 uses only one intermediate disc andis especially suitable for light and medium service. Cor# responding parts are designated with identi` calnumbers as in the Figures 1 and 2 increased by one hundred. The` fast sleeve 104 is supported in a ball bearing 161 which is held lin place in theV cover107 by an end plate 162. A dash ring 163 held frictionally on the sleeve 4 throws oif any lubricant chamber. The counterweights 126 and 127 are arranged on both sides of and close to the single intermediate disc 1-10. The housing 117 is turned down on the outside'to form a seat 165 for, fastening the complete gear to an end plate 166 of anelectromotor or to a suitable bracket.

In the Figures 6 and 7 the shape of two different curves for the intermediate disc are shown of which the curve on Figure 6 is the equidistant to an epicycloid 29 and the' curve on `Figure 7 the equidistant to a prolate epitrochoid 31. The pointsBO on the equidistant have to carry the load during a longer time than the rest of the curve due to the reversal of the curve 29 in the points 28. This disadvantage is entirely removed in a prolate trochoid where the distance e of the tracing point 32 from the center is ing circle as indicated by 34. The distance e of course must correspond exactly with the eccentricity of the crank. A method and means forproducing such curves is described in my copending application, production of` cycloidal curves, Serial No. 151,799, iiled November 30, 1926.4

Having now particularly described and ascertained the nature of my said invention I do not wish to be understood as limiting myself to the exact details of construction as obviously many modifications will occur to a `person skilled in the art. l

What I claim is:

1. In a gear transmission a fast. rotating member, a. slowly rotating member, an eccentric on said fast rotating member, a disc mounted toturn on said eccentric, the cirous cycloidal curve, members to engage with said cycloidal curve, and means for connecting said disk and said slowly rotating member.

2. In a gear transmission a fast rotating member, a slowly rotating member, an eccentric on said fast rotating member, a dise mounted to turn on said eccentric, the circumference of said disc forming the equidis tant to a. continuous cycloidal curve, members Ato engage with saidequidistantj and l tant, and lmeans for connecting sai means for connecting said disk and said slowly rotating member.

`3. In a gear transmission a fast rotating member, a` slowly rotating member, an ec-V centric on said fast rotating member, a disc mounted to turn on said eccentric, the circumference of said disc forming lthe equidistan-'g to a continuous epitroch/oidal curve, members in engagement with said equidistant, and means foi' connecting said `disk and said slowly rotating member.

4. In a gear transmission a fast' rotating member, a slowly rotating member, an eccentric, on said fast rotating member, adisc mounted rotatably on said eccentric, the circumference of said disc forming lthe equidistant to a continuous rolate epitrochoid of which the distance of t e generating point from the center of the rolling circle equals about zvof the radius of the rolling circle, members in engagement with said uidd'i is and said slowly rotating member.

` 5. In a gear transmission a fast rotating.

member, a slowly rotating member, two eccentric portions on said fast member, disposed at 180 to each other,'tWo discs one on each eccentric portion for removing any bending strain from said fast rotating member, the circumference of said. discs forming a continuous cycloidal curve, members in engagement with said discs, and means for connecting said disk to said slowly rotating member.

6. In a gear transmission a fast rotating member, a .slowly rotating member, a li'irality of eccentric ortions on said ast rotating member, a p urality of discs one on 'each eccentric portion, the circumference of eachdisc forming a continuous cycloidall curve, stationary members in enga ement withV said discs, and a plurality o dogs fastened in said slowl frotating member for transferring the load between said discs and said slowly rotating member.

7. In a gear transmission a fast rotating i member, a slowly rotating member, a plurality of eccentric portions on s aid fast rotating member., a plurality of discs, arranged rotatably one on each said eccentric portion,

the circumference of each disc forming acontinuous cycloidal curve, stationary members in engagement with said discs, and a plurality of dogs fastened -in said slowly rotating member for transmittin the load between said discsV and said slow yl rotatingv member, the number of teeth on each disc amultiple of the total number of discs emplyed and the number of dogs in identical number with the number of teeth on `the discs. v

8. In a geartransmission a `fast rotating member, a. slowly rotating-member, an eccentric portion on said fast rotating member, a

disc rotatable on said eccentric, the circum? mission me ference formed'with a continuous cycloidal curve, members in engagement with said cycloidal curve, and dogs in engagement with said disc said dogs dimensioned to permit of slight deflections for equalizing any inaccuracies.

9. In a gear transmission a fast rotating member, .-a slowly rotating member, an eccentric portion on said fast rotating member, a disc rotatable on said eccentric, the circumference an equidistant to a continuous cycloidal curve, rolling members in engagement with said curve, and pinsv for said rolling members of such size as to permit of slight deflections curacies. V

10. In a ear transmission a -fast rotating member, a s owly rotating member, an eccentric portion on said fast rotating member, a

disc rotatable on said eccentric with the circumference a continuous cycloidal curve, stationary members in engagement with said cycloidal curve, a plurality of dogs fastened in said slowly rotatin member, said dogs transmitting'the turning moment between for equalizing anyv inac said slowly rotating shaft and said disc, and

a sup orting ring for said dogs.

11. n a gear transmission a fast rotating Vmember, a slowly rotating member, a pluralit of eccentrics onsaid fast rotating mission member rotatably and eccentrically ity of rings for supporting mounted on said driving member, said transmission member having a toothed portion, a plurality of ckets in said transmission member, eacllimof said ockets extendin partially into one of tlie teeth of sai toothed portion, a `plurality of members rotatable relative to each other and-to said driving member, means on one of said plurality of members for engaging the toothed vportion of said transmission member, land* lplurality of memmeans on another of said bers for engaigaing the poc -13. In a ear transmissiomthe combina tion with a gast rotating member, of a' slowly rotating member, an eccentric portion on said fast rotating member, engaging means mounted to turn on saideccentric portion,

ets in said trans'- other engaging means to engage with said engagin means on .the eccentric portion, one of sai enga 'ng means comprising a curved surface forming substantially an equidistant to a prolatetrochoid, and means operatively lilo connecting the engagin means on the eccenber.

14. AIn a gear transmission, the combina.`

tion with a fast rotating member, of a slowly Arotating member, an eccentric portion on said fast rotating member, engaging lmeans mounted to turn on said eccentric portion, stationar engaging means for cooperation with sai irst named` engaging means, one i of said engaging means comprising a curved surface forming substantially an equidistarit to a prolate trochoid and the other of said en gagng means comprising means for contacting withvsaid curved surface at a plurality of spaced points, and an operative connection between said engaging means on said ec- (tzentric portion and said slowly rotating meml 15. In angear transmission, the combination with a fast rotating member, of a slow- Vly rotating member, an eccentric portion on said fast rotating member, engaging means mounted `to turn on said eccentric rtion, engaging means for cooperation with said first namedA engaging means, one of said en gaging means com rising a curved surface forming substantial y an equidstant to a continuous prolate trochoid and the other of said engaging means comprising means for contacting with said curved surface at a pluralit)T of spaced points, and an operative connection between one of said engaging means and said slowly rotating member.

LORENZ KONRADBRAREN. 

